It’s no surprise that Arctic sea ice is thinning. What is new is just how long, how steadily, and how much it has declined. Univ. of Washington researchers compiled modern and historic measurements to get a full picture of how Arctic sea ice thickness has changed. The results show a thinning in the central Arctic Ocean of 65% between 1975 and 2012.
Sea levels from New York to Newfoundland jumped up about four inches in 2009 and 2010 because...
Rivers and streams could be a major source of antibiotic resistance in the environment. The...
Ocean currents have been carrying floating debris into all five of the world’s major oceanic gyres for decades. However, exactly how much plastic is making its way into the world’s oceans and from where it originates has been a mystery— until now.
In shallow waters around the world, where nutrient pollution runs high, oxygen levels can plummet to nearly zero at night. Oysters living in these zones are far more likely to pick up the lethal Dermo disease.
Coral reefs are the jungles of the oceans, home to some of the planet’s most fertile fishing grounds, and hotspots of global tourism.
Acoustic-gravity waves can be generated by underwater earthquakes, explosions and landslides, as well as by surface waves and meteorites. A single one of these waves can stretch tens or hundreds of kilometers, and travel at depths of hundreds or thousands of meters below the ocean surface, transferring energy from the upper surface to the seafloor, and across the oceans. Acoustic-gravity waves often precede a tsunami or rogue wave.
Seafloor sediment cores reveal abrupt, extensive loss of oxygen in the ocean when ice sheets melted roughly 10,000 to 17,000 years ago, according to a study. The findings provide insight into similar changes observed in the ocean today. In the study, researchers analyzed marine sediment cores from different world regions to document the extent to which low oxygen zones in the ocean have expanded in the past, due to climate change.
A technology developed by Stanford Univ. scientists for passively probing the seafloor using weak seismic waves generated by the ocean could revolutionize offshore oil and natural gas extraction by providing real-time monitoring of the subsurface while lessening the impact on marine life.
Satellite images have revealed that a remote Arctic ice cap has thinned by more than 50 m since 2012 and that it’s now flowing 25 times faster. A team led by scientists from the Centre for Polar Observation and Modelling (CPOM) at the Univ. of Leeds combined observations from eight satellite missions, including Sentinel-1A and CryoSat, with results from regional climate models, to unravel the story of ice decline.
Researchers who are building the highest-resolution map of the Greenland Ice Sheet to date have made a surprising discovery: two lakes of meltwater that pooled beneath the ice and rapidly drained away. One lake once held billions of gallons of water and emptied to form a mile-wide crater in just a few weeks. The other lake has filled and emptied twice in the last two years.
Scientists plumbing the depths of the ocean have made a surprise finding that could change the way we understand supernovae, exploding stars way beyond our solar system. They have analyzed extraterrestrial dust thought to be from supernovae that has settled on ocean floors to determine the amount of heavy elements created by the massive explosions.
The world's oceans are now rising far faster than they did in the past, a new study says. The study found that for much of the 20th century the sea level was about 30% less than earlier research had figured. But that's not good news, scientists say, because about 25 years ago the seas started rising faster and the acceleration in 1990 turns out to be more dramatic than previously calculated.
As the largest single chunk of melting snow and ice in the world, the massive ice sheet that covers about 80% of Greenland is recognized as the biggest potential contributor to rising sea levels due to glacial meltwater. Until now, however, scientists’ attention has mostly focused on the ice sheet’s aquamarine lakes and on monster chunks of ice that slide into the ocean to become icebergs.
Scientists who have reported that the Great Lakes are awash in tiny bits of plastic are raising new alarms about a little-noticed form of the debris turning up in sampling nets: synthetic fibers from garments, cleaning cloths and other consumer products. They are known as "microfibers", exceedingly fine filaments made of petroleum-based materials such as polyester and nylon that are woven together into fabrics.
Fertilizers are known to promote the growth of toxic cyanobacterial blooms in freshwater and oceans worldwide, but a new multi-institution study shows the aquatic microbes themselves can drive nitrogen and phosphorus cycling in a combined one-two punch in lakes.
Off the West Coast of the United States, methane gas is trapped in frozen layers below the seafloor. New research from the University of Washington shows that water at intermediate depths is warming enough to cause these carbon deposits to melt, releasing methane into the sediments and surrounding water.
A National Science Foundation-funded research team has successfully tested an autonomous underwater vehicle (AUV) that can produce high-resolution, 3-D maps of Antarctic sea ice. SeaBED, as the vehicle is known, measured and mapped the underside of sea-ice floes in three areas off the Antarctic Peninsula that were previously inaccessible.
Using ocean observations and a large suite of climate models, Lawrence Livermore National Laboratory (LLNL) scientists have found that long-term salinity changes have a stronger influence on regional sea level changes than previously thought.
The continental margins of plates on either side of the Atlantic Ocean are thinner than expected, and an international team led by a Rice Univ. scientist is using an array of advanced tools to understand why. The viscous bottom layers of the continental shelves beneath the Gibraltar arc and northeastern South America are literally being pulled off by adjacent subducting oceanic plates.
Scientists have identified a mechanism that could be a big contributor to warming in the Arctic region and melting sea ice. The research was led by scientists from Lawrence Berkeley National Laboratory. They studied a long-wavelength region of the electromagnetic spectrum called far infrared. It’s invisible to our eyes but accounts for about half the energy emitted by the Earth’s surface. This process balances out incoming solar energy.
To understand the extent to which human activities are polluting Earth’s atmosphere and oceans, it’s important to distinguish human-made pollutants from compounds that occur naturally. A recent study co-authored by a Brown Univ. professor does just that for ammonium, a compound that is produced by human activities like agriculture, as well as by natural processes that occur in the ocean.
Where's the remaining oil from the 2010 Deepwater Horizon disaster in the Gulf of Mexico? The location of 2 million barrels of oil thought to be trapped in the deep ocean has remained a mystery. Until now: A national team of scientists has discovered the path the oil followed to its resting place on the Gulf of Mexico sea floor.
Methane-breathing microbes that inhabit rocky mounds on the seafloor could be preventing large volumes of the potent greenhouse gas from entering the oceans and reaching the atmosphere, according to a new study. The rock-dwelling microbes represent a previously unrecognized biological sink for methane and as a result could reshape scientists' understanding of where this greenhouse gas is being consumed in subseafloor habitats.
Using satellite observations and a large suite of climate models, Lawrence Livermore National Laboratory scientists have found that long-term ocean warming in the upper 700 m of Southern Hemisphere oceans has likely been underestimated.
Scientists have created a new map of the world's seafloor, offering a more vivid picture of the structures that make up the deepest, least-explored parts of the ocean. The feat was accomplished by accessing two untapped streams of satellite data, which has allowed thousands of previously uncharted mountains rising from the seafloor, called seamounts, to be revealed on the map, along with new clues about the formation of the continents.
The most comprehensive assessment conducted by the Ocean Health Index rates the Earth’s oceans at 67 out of 100 in overall health. In addition, for the first time, the report assessed the Antarctic and the 15 ocean regions beyond national jurisdiction (high-seas areas). Together with the 220 exclusive economic zones (EEZs) measured in 2012 and 2013, the index now measures all of the oceans on planet Earth.
Brine shrimp, which are sold as pets known as sea-monkeys, are tiny—only about half an inch long each. With about 10 small leaf-like fins that flap about, they look as if they could hardly make waves. But get billions of similarly tiny organisms together and they can move oceans.
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